Surgical instrument for graft harvesting

ABSTRACT

Instruments and methods for harvesting a tissue structure such that a tendon graft are provided. In general, the surgical instrument includes an elongate shaft and an end effector pivotally coupled to a distal end thereof. The end effector defines a tissue seating passage configured to seat therethrough a portion of the tendon when the end effector is in use. The end effector is configured to be manipulated such that either its first or second end is positioned as a leading end. A method for using the end effector to harvest a tendon includes using the end effector to strip and cut the tendon at one end thereof when the first end of the end effector is a leading end, manipulating the end effector such that its second end becomes the leading end, and using the end effector to strip and cut the tendon at another, opposite end thereof.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. Ser. No. 16/565,880entitled “A Surgical Instrument for Graft Harvesting” filed Sep. 10,2019, which is a divisional of U.S. patent application Ser. No.14/731,058 (now U.S. Pat. No. 10,448,935) entitled “A SurgicalInstrument for Graft Harvesting” filed Jun. 4, 2015, which are herebyincorporated by reference in their entireties.

FIELD

A surgical instrument for graft harvesting as well as methods for usingsuch surgical instrument are provided.

BACKGROUND

A ligament is a piece of fibrous tissue which connects one bone toanother within the body. Ligaments are frequently damaged (e.g.,detached, torn or ruptured) as the result of injury or accident. Adamaged ligament can impede proper stability and motion of a joint andcause significant pain. A damaged ligament can be replaced or repairedusing various procedures, a choice of which can depend on the particularligament to be restored and on the extent of the damage. When ligamentsare damaged, surgical reconstruction can be necessary, as the ligamentsmay not regenerate on their own.

An example of a ligament that is frequently damaged as a result ofinjury, overexertion, aging and/or accident is the anterior cruciateligament (ACL) that extends between a top of the tibia and a bottom ofthe femur. Other ligaments that are often damaged and may need to bereplaced include a posterior cruciate ligament (PCL) and medialcollateral ligament (MCL). A damaged ACL, PCL, or MCL can causeinstability of the knee joint, arthritis, and substantial pain.

ACL reconstruction or repair typically includes the use of a tendongraft replacement procedure which usually involves, for example,drilling a bone tunnel through the tibia and the femur. Then a graft,which may be an artificial ligament or harvested graft, such as atendon, is secured at the sites where the natural ligament attaches.

Harvesting a tendon graft can be a challenging task that can define theoutcome of the ACL reconstruction procedure. A number of conventionalprocedures exist for harvesting a tendon graft from a donor site.However, many existing approaches have certain shortcomings. Forexample, a traditional incision for graft harvesting is made anteriorly,at a location in the subject's knee where the semitendinosus andgracilis tendons are not separate tendons, which can complicateidentification of the tendons. Furthermore, accessory bands arising fromthe semitendinosus and gracilis tendons can complicate tendon harvestingby diverting a harvesting instrument such that the main tendon can becut short at the accessory band level. Such premature amputation of thetendon can result in a graft that is too short to allow adequate ACLreconstruction.

Accordingly, there is a need for improved graft harvesting instrumentsand techniques for using such instruments.

SUMMARY

A surgical instrument is provided that in some aspects can include anelongate shaft having a longitudinal axis, a proximal end, and a distalend, and an end effector mounted on the distal end of the elongateshaft. The end effector can have first and second ends and it isconfigured to receive and seat a length of tissue, and it includes atissue seating passage extending substantially parallel to thelongitudinal axis of the shaft in an operative position that is definedat least in part by an arcuate inner wall. The end effector is pivotallymounted on the shaft such that the end effector is configured to berotatably manipulated during a procedure such that the first end of theend effector can be selectively positioned to be one of a leading endand a trailing end.

The end effector can vary in a number of ways. For example, the endeffector can include a tissue retaining portion including the tissueseating passage and a connecting portion coupled to the tissue retainingportion and configured to rotatably couple the end effector to thedistal end of the elongate shaft. The distal end of the elongate shaftcan have a longitudinal slot configured to rotatably seat therein theconnecting portion of the end effector. At least one of the first andsecond ends of the end effector can have a sharp edge. One of the firstand second ends of the end effector can have a sharp protrusionextending beyond at least one member having the arcuate inner wall.

The tissue retaining portion can vary in a number of ways. For example,the tissue retaining portion can include a base portion andlongitudinally spaced apart first and second arcuate members extendingfrom and coupled to the base portion at opposite sides of a longitudinalaxis of the base portion so as to define the tissue seating passage. Thetissue retaining portion can be in the form of a substantially tubularmember. The tubular member can have at least one slot formed thereinalong a length thereof. The at least one slot can be curved.

The surgical instrument can further include a handle coupled to theproximal end of the elongate shaft. In some aspects, the surgicalinstrument can include at least one locking feature configured to lockthe end effector in a first position when the first end thereof ispositioned to be the leading end or to lock the end effector in a secondposition when the second end thereof is positioned to be the leadingend.

A surgical instrument is also provided that in some aspects includes anelongate shaft having a longitudinal axis, a proximal end, and a distalend; and a tissue cutting guide pivotally mounted to the distal end ofthe elongate shaft, the tissue cutting guide being selectivelypositionable adjacent one of a first side of the shaft and an opposedsecond side of the shaft, wherein a first end of the tissue cuttingguide is a leading end of the tissue cutting guide when it is positionedadjacent the first side of the shaft and wherein the first end of thetissue cutting guide is a trailing end of the tissue cutting guide whenit is positioned adjacent the second side of the shaft.

The tissue cutting guide can vary in a number of ways. For example, thetissue cutting guide can include a tissue retaining portion defining atissue seating passage, and a connecting portion coupled to the tissueretaining portion and configured to pivotally couple the tissue cuttingguide to the distal end of the elongate shaft. The tissue retainingportion can include two spaced apart arcuate arms extending fromopposite ends of the connecting portion, the arcuate arms being curvedin opposite circumferential directions along a length of the connectingportion. The tissue retaining portion can be in the form of asubstantially cylindrical elongate member.

A method of harvesting a tissue structure is also provided that in someaspects includes inserting a surgical instrument including an elongateshaft and an end effector coupled to a distal end of the elongate shaftinto an incision adjacent a mid-point of the tissue structure, the endeffector having first and second ends and being pivotally mounted on theshaft to be rotatably manipulated such that the first end of the endeffector can be selectively positioned to be one of a leading end and atrailing end. The method also includes coupling the end effector to thetissue structure near the mid-point thereof such that a portion of thetissue structure extends through a tissue seating passage defined by theend effector; with the first end positioned to be the leading end, thesecond end positioned to be the trailing end, and the end effectorcoupled to the tissue structure, advancing the end effector along thetissue structure from the mid-point towards a first end of the tissuestructure; and stripping and cutting the tissue structure at the firstend thereof. The method further includes, after the tissue structure iscut at the first end thereof, returning the end effector coupled to thetissue structure to a location near the incision; manipulating the endeffector such that the second end thereof is positioned to be theleading end, and the first end thereof is positioned to be the trailingend; with the second end of the end effector positioned to be theleading end, the first end of the end effector positioned to be thetrailing end, and the end effector coupled to the tissue structure,advancing the end effector along the tissue structure from the locationnear the incision towards an opposite, second end of the tissuestructure; and stripping and cutting the tissue structure at the secondend thereof.

The method can vary in a number of ways. For example, the method canfurther include, after the tissue structure is cut at the first endthereof, withdrawing the first end of the tissue structure from theincision. The inserting step can be conducted through a posteriorincision. The tissue structure is at least one of the gracilis tendonand semitendinosus tendon. The first end of the tissue structure can bea proximal end, and the second end of the tissue structure can be adistal end.

In some aspects, after the tissue structure is cut at the first endthereof, the end effector coupled to the tissue structure is returned tothe location near the incision without removing the end effector fromwithin the incision. Manipulating the end effector can include pivotallyrotating the end effector with respect to the shaft. The tissuestructure can be a tendon, nerve or vein.

BRIEF DESCRIPTION OF THE DRAWINGS

The embodiments described above will be more fully understood from thefollowing detailed description taken in conjunction with theaccompanying drawings. The drawings are not intended to be drawn toscale. For purposes of clarity, not every component may be labeled inevery drawing. In the drawings:

FIG. 1A is a perspective view of one embodiment of a surgical device;

FIG. 1B is a perspective exploded view of a distal end of the surgicaldevice of FIG. 1A;

FIG. 2A is a perspective view of a distal end of the surgical device ofFIG. 1A;

FIG. 2B is a front perspective view of the distal end of the surgicaldevice of FIG. 1A;

FIG. 2C is a side view of the distal end of the surgical device of FIG.1A;

FIG. 3A is a side view of the distal end of the surgical device of FIG.1A showing an end effector having a first end positioned to be a leadingend;

FIG. 3B is a side view of the distal end of the surgical device of FIG.3A showing the end effector having a second end positioned to be aleading end;

FIG. 3C is a cross-sectional view of a distal end of an elongate shaftof a surgical instrument and a connecting portion of an end effector ofthe surgical instrument configured to be coupled to one another via alocking mechanism;

FIG. 3D is another cross-sectional view of the distal end of theelongate shaft and the connecting portion of FIG. 3C;

FIG. 4A is a side view of another embodiment of a surgical deviceshowing an end effector having a first end positioned to be a leadingend;

FIG. 4B is a side view of the surgical device of FIG. 4A showing the endeffector positioned such that a tissue seating passage extendingtherethrough is approximately perpendicular to a longitudinal axis ofthe surgical device;

FIG. 4C is a side view of the surgical device of FIG. 4A showing the endeffector having a second end positioned to be a leading end;

FIG. 5 is a perspective view of one embodiment of an end effector of asurgical instrument;

FIG. 6 is an end view of another embodiment of an end effector of asurgical instrument;

FIG. 7 is a perspective view of one embodiment of an end effector of asurgical instrument; and

FIGS. 8A-8F are schematic illustrations of one embodiment of a method ofharvesting a tendon using a described surgical instrument.

DETAILED DESCRIPTION

Certain exemplary embodiments will now be described to provide anoverall understanding of the principles of the systems and methodsdisclosed herein. One or more examples of these embodiments areillustrated in the accompanying drawings. Those skilled in the art willunderstand that the systems and methods specifically described hereinand illustrated in the accompanying drawings are non-limiting exemplaryembodiments and that the scope of the embodiments is defined solely bythe claims. Further, the features illustrated or described in connectionwith one exemplary embodiment may be combined with the features of otherembodiments. Such modifications and variations are intended to beincluded within the scope of the described embodiments.

The embodiments described herein generally relate to instruments andmethods for harvesting tendon grafts for ligament reconstruction oraugmentation surgeries. However, the described techniques can also beused for harvesting other anatomical structures, such as, for example,nerves and veins. A surgical instrument is provided that includes anelongate shaft and an end effector pivotally mounted on a distal end ofthe shaft. The end effector defines a tissue seating passage extendingbetween first and second ends thereof and configured to receive aportion of the tendon when the surgical instrument is in use. The endeffector can be rotatably manipulated to be positioned at multipleangles with respect to a longitudinal axis of the elongate shaft whilethe tendon remains associated with the tissue seating passage. In anoperative position, the end effector can be positioned such that thetissue seating passage is substantially parallel to the longitudinalaxis of the elongate shaft and one of the first and second ends of theend effector is selectively positioned as a leading or trailing end ofthe end effector. The leading end is used to strip and cut the tendon.Thus, the end effector allows one to strip and to cut both ends of thetendon by positioning either the first or second end of the end effectoras a leading end. In some aspects, the first and second ends can have aconfiguration that facilitates harvesting a tendon at a location havingcertain anatomical characteristics.

A method of harvesting a tendon including using a surgical instrument asdescribed herein is also provided. The method involves making anincision adjacent a mid-point of the tendon and coupling the surgicalinstrument to the tendon. In the illustrated embodiments, the incisionis a posterior incision made on the back of a patient's knee. Theposterior incision facilitates easy identification of a tendon, such asthe semitendinosus or gracilis tendon, because at that location thesetendons are present as separate tendons.

A first end of the end effector of the surgical instrument can bepositioned as a leading end whereas a second end of the end effector isa trailing end. The effector is then advanced along the tendon from themid-point towards a first end of the tendon to then strip and cut thetendon at its first end. After the tendon is cut at its first end, thesurgical instrument is brought back to a location near the incision andthe end effector is manipulated (e.g., rotated with respect to anelongate shaft of the instrument) such that the second end of the endeffector becomes a leading end while the first end is now positioned asa trailing end. The end effector, which remains coupled to the tendon,can then be advanced from the mid-point towards a second end of thetendon to then strip and cut the tendon at its second end.

The instruments and methods described herein provide a number ofadvantages over existing techniques for harvesting tendons. For example,the described techniques reduce a risk of premature amputation of thetendon. This increases a possibility of a success of the procedure anddecreases a chance of unnecessary damage to a tendon and trauma to thepatient. Also, patient satisfaction can be improved since the incisionis located on the back of the patient's knee and is thus less visible.Furthermore, the described surgical instrument enables harvesting atendon at its both ends while the instrument remains associated with thetendon. Because the posterior incision is made to access a tendon, thesurgical instrument can have a smaller length as compared toconventional stripping instruments, which facilitates operation of thesurgical instrument. In addition, the first and second ends of the endeffector of the surgical instrument can be configured to facilitategraft harvesting at specific anatomical locations when the ends are usedas leading ends.

The described instruments and methods can be used in conjunction withharvesting various tendons, such as the gracilis and semitendinosustendons, which can then be used in a variety of different surgicalcontexts. Furthermore, harvested tendon grafts can be utilized inconnection with surgical procedures for repairing or replacing ligamentsin a variety of joints. In some embodiments, tendon grafts harvested asdescribed herein have particular utility in cruciate ligamentreconstruction procedures such as, for example, the cruciate ligamentsof the knee.

FIGS. 1A, 1B and 2A-2C illustrate one example of a surgical instrument100 for harvesting a tendon. The surgical instrument 100 includes atissue cutting guide or an elongate shaft 102 having proximal and distalends 102 p, 102 d and a longitudinal axis A extending therethrough. Asshown in FIG. 1A, the elongate shaft 102 can be coupled at the proximalend 102 p thereof to a handle 104 configured to hold and manipulate thesurgical instrument 100. The surgical device 100 also includes an endeffector 106 pivotally mounted on the distal end 102 d of the elongateshaft 102. The surgical instrument 100 can be formed from any suitablematerial, for example, a metal or polymer.

As shown, the elongate shaft 102 is a generally cylindrical elementhaving the handle 104 coupled proximally thereto. The outer surface ofthe elongate shaft 102 can be generally smooth and the elongate shaft102 or a portion, such as a distal portion, thereof can be distallytapered to facilitate insertion of the instrument 100 into an incisionin a subject's body. As shown in FIG. 1B, the distal end 102 d of theelongate shaft 102 has a longitudinal slot 108 configured to pivotallyseat therein the end effector 106, as discussed in more detail below.The elongate shaft 102 can have any suitable dimensions. For example, alength of the elongate shaft 102 can range from about 20 cm to about 30cm. In one aspect, the length of the elongate shaft 102 can be about 28cm. A diameter of the elongate shaft 102 can range from about 3 mm toabout 7 mm. In one aspect, the diameter of the elongate shaft 102 at itsdistal end 102 d can be about 4 mm. However, a person skilled in the artwill understand that the elongate shaft 102 can have other dimensions.

The handle 104 can have a variety of configurations and sizes, as thedescribed embodiments are not limited in this respect. The handle 104can have suitable features that facilitate grip such that the handle 104can be conveniently used to hold and operate the surgical instrument100. In some aspects, a length of the handle can range from about 10 cmto about 20 cm. In one aspect, the length of the handle 104 can be about11 cm.

As shown in FIGS. 1B, 2A and 2B, the end effector 106 includes a tissueretaining portion 110 and a connecting portion 112 coupled to the tissueretaining portion 110 and configured to rotatably couple the endeffector 106 to the distal end 102 d of the elongate shaft 102.

The tissue retaining portion 110 can have a variety of configurations.In the illustrated embodiment, the tissue retaining portion 110 isgenerally cylindrical and has a base portion 116 and longitudinallyspaced apart first and second arcuate members 118 a, 118 b extendingfrom and coupled to the base portion 116 at opposite sides of alongitudinal axis B (FIG. 1B) of the base portion 116. The first andsecond arcuate members 118 a, 118 b are curved towards one another in a“pig-tail” configuration so as to define a tissue seating passage 114defined at least in part by arcuate inner walls of the first and secondarcuate members 118 a, 118 b. The tissue seating passage 114 extendssubstantially parallel to the longitudinal axis A of the elongate shaft102 in an operative position, as described in more detail below. Thetissue seating passage 114 is configured to receive a portion of thetendon extending therethrough when the surgical instrument 100 is inuse. As shown in FIG. 2B, the first and second arcuate members 118 a,118 b are coupled to the base portion 116 such that their inner arcuatewalls defining the tissue seating passage 114 are aligned along the baseportion 116. In the illustrated embodiment, the tissue seating passage114 has a round or oval cross-sectional shape. However, the tissueseating passage can have other configurations and variouscross-sectional shapes. For example, in some aspects, the tissueretaining portion can include more than two arcuate members extendingfrom and coupled to the base portion. Furthermore, some or all of thearcuate members can be coupled at the same side of the base portion.

The outer side walls of the first and second arcuate members 118 a, 118b define first and second ends 107 a, 107 b of the end effector 106. Thefirst and second ends 107 a, 107 b have a shape that is based on aconfiguration of the end effector. Thus, in the illustrated example, thefirst and second ends 107 a, 107 b are shaped as arcuate outer sidewalls of the end effector 106.

The end effector 106 can pivot with respect to the elongate shaft 102such that each of the first and second ends 107 a, 107 b can beselectively positioned to be a leading or trailing end, depending on anorientation of the end effector 106 with respect to the shaft 102. Forexample, when the end effector 106 is positioned adjacent to one side ofthe elongate shaft 102 as shown in FIGS. 1A, 1B, and 2A-2C, the firstend 107 a is positioned as the leading or forward end of the surgicaldevice 100 whereas the second end 107 b is positioned as the trailingend.

As shown in FIGS. 1A, 1B, 2A and 2C, the first and second arcuatemembers 118 a, 118 b are longitudinally spaced apart such that a slot orgap 119 (FIG. 2C) is formed therebetween. The gap 119 can have a widthselected so as to facilitate coupling a tendon with the end effector106. For example, in some aspects, the gap 119 can range from about 2 mmto about 7 mm. In one example, the gap 119 can be about 5 mm.Furthermore, it should be appreciated that the end effector can beconfigured to have a slot or gap having other configurations thatfacilitate coupling the end effector to a tendon. For example, the slotof a suitable width can be a spiral slot or a slot having any othershape. The slot can extend approximately along a length of the endeffector.

Referring back to FIG. 1B, the end effector 106 includes the connectingportion 112 that is coupled to the tissue retaining portion 110 and thatcan have various configurations. In the illustrated example, theconnecting portion 112 extends downward from the base portion 116 of thetissue retaining portion 110. The connecting portion 112 can beintegrally or monolithically formed with the base portion 116 or it canbe a separate component coupled (e.g., welded) to the base portion 116in a suitable manner. The connecting portion 112 is configured topivotably fit within the longitudinal slot 108 extending through thedistal end 102 d of the elongate shaft 102. The slot 108 is formed suchthat, when the end effector 106 is inserted therein, the connectingportion 112 can pivotally rotate relative to the longitudinal axis A ofthe elongate shaft 102 such that the first end 107 a of the end effector106 can be selectively positioned to be one of a leading end and atrailing end.

In the illustrated example, the connecting portion 112 is generallytriangular-shaped and approximately resembles an isosceles triangle witha longer base edge 117 a coupled to the base portion 116 and two otheredges 117 b, 117 c having an equal length, shorter than that of the baseedge 117 a, extending from the base portion 116 towards the end effector106. However, a person skilled in the art will appreciate that theconnecting portion 112 can have other configurations. For example, theconnecting portion can be shaped as equilateral triangle, it can berectangular, or it can have any other shape.

As shown in FIG. 1B, the connecting portion 112 includes an opening 120extending therethrough that is disposed approximately mid-way betweenthe edges 117 b, 117 c. The connecting portion 112 is configured to fitwithin the longitudinal slot 108 such that the opening 120 is alignedwith openings 122 a, 122 b formed in opposed walls of the distal end 102d of the elongate shaft 102 separated by the slot 108. The openings 122a, 122 b at the distal end 102 d and the opening 120 within theconnecting portion 112 can receive a pin 124 therethrough that thuspivotally couples the connecting portion 112 of the effector 106 to theelongate shaft 102. A person skilled in the art will appreciate thatother mechanisms can be used to rotatably couple the effector 106 to theelongate shaft 102, as described embodiments are not limited in thisrespect. For example, the mechanisms can include a variety of hinges,ball-and-socket joints and any other mechanisms.

Although in the illustrated examples, the end effector 106 is configuredto rotate within a single plane as permitted by the configuration of theslot 108, in other aspects, the end effector can be positioned atmultiple planes with respect to the elongate shaft (e.g., when acoupling such as a ball-and-socket joint is used). Furthermore, thesurgical instrument in accordance with the description here can includea locking mechanism configured to releasably retain the end effector ina certain orientation with respect to the elongate shaft. As anothervariation, the end effector can be configured and coupled to theelongate shaft such that the end effector can be positioned at differentangles with respect to opposite sides of the elongate shaft. In otherwords, the end effector can be “biased” towards one of the sides of theelongate shaft.

The end effector 106 can have any suitable dimensions. For example, insome aspects, the overall length of the end effector 106 can range fromabout 3 mm to about 25 mm. In some in some aspects, the length of theend effector 106 can range from about 10 mm to about 15 mm. In oneaspect, the length of the end effector 106 can be about 11 mm. Adiameter of the end effector 106 can range from about 3 mm to about 7mm. In one aspect, the diameter of the end effector 106 is about 4 mm.However, a person skilled in the art will understand that the endeffector 106 can have other dimensions. Furthermore, the end effectorcan have irregular shapes, such as oval, bowtie-shaped, bean-shaped,kidney-shaped, or other shapes, in which cases a size of the endeffector will vary depending on an intended size of an incision,patient's characteristic and other factors.

As mentioned above, the end effector 106 is pivotally mounted on theelongate shaft 102 such that the end effector 106 can be rotatablymanipulated during a graft harvesting procedure. The tissue seatingpassage 114 of the end effector 106 can receive therein a portion of atendon being harvested and the end effector 106 can be manipulated toallow either of its ends to be a leading end. As shown in FIGS. 3A and3B, the end effector 106 can be manipulated such that its first end 107a is selectively positioned to a leading end or a trailing end. In theillustrated examples, the end effector 106 is configured to rotateapproximately 180 degrees with respect to the longitudinal axes A of theelongate shaft 102.

Thus, FIG. 3A shows that, when the end effector 106 extendssubstantially parallel to the longitudinal axis A of the elongate shaft102 adjacent a first side 103 a of the shaft 102, the first end 107 a ofthe end effector 106 is positioned as a leading end. Thus, in suchconfiguration, the first end 107 a of the end effector 106 can be usedto strip a tendon from the surrounding muscle and other soft tissue andthen cut the tendon at a first end thereof. For example, the first end107 a of the end effector 106 can be used to strip and cut a proximalend of the tendon. However, as shown in FIG. 3B, when the end effector106 is pivoted with respect to the elongate shaft 102 such that the endeffector 106 extends substantially parallel to the longitudinal axis Aof the elongate shaft 102 adjacent a second, opposite side 103 bthereof, the first end 107 a is positioned as a trailing end and thesecond end 107 b is positioned as a leading end. When used as theleading end, the second end 107 b can be used to strip and cut thetendon at a second, opposite end of the tendon. For example, second end107 b of the end effector 106 can be used to strip and cut a distal endof the tendon. However, a person skilled in the art will appreciatethat, depending on a configuration of the end effector, either end ofthe end effector can be used to strip and cut either end of the tendon.

In some implementations of the current techniques, the surgicalinstrument can be configured such that a position of the end effectorwith respect to the elongate shaft can be reversibly locked. Forexample, the surgical instrument can have one or more locking featuresthat allow the end effector to be locked in a first position when itextends along one side of the elongate shaft such that a first end ofthe end effector is positioned as a leading end. The end effector canalternatively be locked or secured in a second position when it extendsalong another, opposite side of the elongate shaft such that a secondend of the end effector is positioned as a leading end. FIGS. 3C and 3Dillustrate an example of such locking mechanism. FIGS. 3C and 3D show across-section of a distal end of an elongate shaft 302 (e.g., elongateshaft 102) of a surgical instrument having a connecting portion 312disposed within a longitudinal slot 308 configured to pivotally seattherein an end effector of the surgical instrument (not shown). Theconnecting portion 312 can be similar to connecting portion 112 (e.g.,FIGS. 1B and 2C) that extends downward from a base portion of a tissueretaining portion defined by the end effector. Dashed lines 313illustrate a location of a through passage configured to receive a pinor other connecting element (e.g., pin 124 in FIG. 1B).

As shown in FIG. 3C, the slot 308 separates the distal end of the shaft302 into first and second arms 303 a, 303 b. In this example, thelocking mechanism can include rounded ridges or protrusions 314 a, 314 bformed on opposite ends of one side of the connecting portion 312 androunded ridges or protrusions 316 a, 316 b formed on opposite ends ofanother, opposite side of the connecting portion 312. The protrusions314 a, 314 b are configured to lockingly mate with respective grooves orrecesses 324 a, 324 b formed on the inner surface of the first arm 303a. Similarly, the protrusions 316 a, 316 b are configured to lockinglymate with respective grooves or recesses 326 a, 326 b formed on theinner surfaces of the second arm 303 b. The protrusions can beconfigured to fittedly mate with the respective recesses such that aforce is required to be applied to both engage and disengage theprotrusions and the recesses. It should be appreciated that theprotrusions and recesses are shown by way of example only, as anysuitable number of any other features can be used to lock or secure aposition of an end effector with respect to the elongate shaft.

In the example of FIG. 3B, it is schematically indicated by an arrow 315indicated that the end effector is shown to be disposed below theelongate shaft 302. It should be appreciated, however, that the positionof the end effector “below” the shaft 302 is shown for illustrationpurposes only, to demonstrate a position when the end effector isdisposed along one end of the elongate shaft such that the end effectoris locked at that position by engaging the protrusions 314 a, 314 b, 316a, 316 b on the connecting portion 312 with the recesses 324 a, 324 b,326 a, 326 b on the distal end of the shaft 302. The end effector canthen be manipulated so as to disengage the protrusions from therespective recesses and position the end effector along an opposite sideof the shaft 302. Thus, as shown by an arrow 317 in FIG. 3D, theeffector can be disposed above the elongate shaft 302. The protrusionscan then be again engaged with the recesses to lock the position of theend effector with respect to the shaft 302. As shown in FIG. 3D, theprotrusions 314 b, 314 a engage with the recesses 324 a, 324 b,respectively. The protrusions 316 b, 316 a engage with the recesses 326a, 326 b, respectively, as also shown in FIG. 3D.

As mentioned above, an end effector of a surgical instrument describedherein can have a variety of configurations. FIGS. 4A-4C illustrate anexample of a surgical instrument 400 having an elongate shaft 402, ahandle 404 coupled to a proximal end 402 p of the elongate shaft 402,and an end effector 406 pivotally coupled to a distal end 402 d of theelongate shaft 402 and having a tubular configuration. As shown in FIGS.4A-4C, the end effector 406 having first and second ends 407 a, 407 bhas a generally tubular configuration such that inner walls of the endeffector 406 define a tissue seating passage 414. In the illustratedexample, the outer wall of the end effector 406 does not have a slotformed therein. Thus, when using such an exemplary device, a tendon willbe inserted into the end effector 406 to extend through the tissueseating passage 414. In other aspects, an end effector can have asimilar tubular configuration and straight or curved slots formed withinthe outer wall of the end effector (e.g., approximately along a lengththereof).

In the example illustrated in FIGS. 4A-4C, the end effector 406 iscoupled to the distal end 402 d of the elongate shaft 402 using amechanism similar to that used to couple end effector 106 to elongateshaft 102 (FIGS. 1A, 1B, 2A-2C, 3A and 3B). However, as shown, in thisexample, a connecting portion 412 of the end effector 406 configured topivotally mount the end effector 406 on the elongated shaft 402 has agenerally rectangular configuration. A person skilled in the art willappreciate, however, that the connecting portion can have any otherconfigurations.

The end effector 406 is configured to be manipulated to be positionedwith respect to the elongate shaft 402 such that the first end 407 a ofthe end effector 406 is a leading end (FIG. 4A) or the second end 407 bof the end effector 406 is a leading end (FIG. 4C). In theconfigurations shown in FIGS. 4A and 4C in which the end effector 406 ispositioned as ready for tendon harvesting, the end effector 406 ispositioned such that the tissue seating passage 414 extendssubstantially parallel to a longitudinal axis A1 of the elongate shaft402. FIG. 4B illustrates the end effector 406 in an intermediateposition in which the end effector 406 extends substantiallyperpendicular to the longitudinal axis A1 of the elongate shaft 402, toillustrate that the end effector 406 can be manipulated to be positionedat different angles with respect to elongate shaft 402.

As mentioned above, a tissue seating passage defined by an end effectorof a described surgical instrument can have various configurations andcross-sectional shapes. For example, regardless of the specificconfiguration of the end effector, the tissue seating passage can have around, oval or other (including irregular) cross-sections. Also, the endeffector can have one or more slots or gaps having a variety ofconfigurations defined therein.

FIG. 5 illustrates one example of an end effector 506 of a surgicalinstrument 500 having a curved cut-out or slot 519. The surgicalinstrument 500 includes other components, such as an elongate shafthaving the end effector 506 pivotally mounted thereon, and any othercomponents, which are not shown in FIG. 5. In this example, the endeffector 506 is a generally tubular member with its inner walls defininga tissue seating passage 514 extending therethrough. The slot 519 isformed along the length of the end effector 506 and is configured topass a portion of a tendon therethrough when the surgical instrument 500is in use. A person skilled in the art will appreciate that the slot 519can be less or more curved and it can form multiple “waves” along thelength of the end effector 506. Furthermore, the slot can be formed suchthat it winds around opposite sides of the end effector. The curvedconfiguration of the slot 519 can facilitate retaining a portion of thetendon within the tissue seating passage 514 when the surgicalinstrument 500 is in use.

FIG. 6 illustrates an example of an end effector 606 of a surgicalinstrument 600 having a “kidney-like” cross-sectional shape.Specifically, as shown in FIG. 6, a top portion 609 of the end effector606 is generally concave. Other configurations can be used additionallyor alternatively.

As mentioned above, the surgical instrument in accordance with thedescribed aspects is configured such that the first and second ends ofthe end effector can selectively operate as either a leading or trailingend. Thus, each of the ends of the effector can be configured to be moresuitable for stripping and cutting a particular portion of a tendonhaving certain anatomical specificities. For example, although the firstand second ends of the end effector can be either both sharp or bothblunt in a uniform manner, in some embodiments, a portion of one or bothof the first and second ends can be sharpened and/or shaped in a certainmanner depending on characteristics of the portion of the tendon to beharvested using that end.

In some aspects, one or both ends of an end effector of a surgicalinstrument can have features that facilitate interaction of theinstrument with anatomical structures and allow harvesting the graftwith a decreased risk of damaging or prematurely amputating the tendon.For example, as known by a person skilled in the art, the accessorybands of the gracilis and semitendinosus tendons separate from arespective main tendon along a similar plane. Thus, an end of the endeffector intended to be used to separate and harvest a distal end of atendon can have features that facilitate this process. This can decreasea possibility of donor site morbidity. Also, using an end effectorhaving ends adapted to anatomical structures within the donor site candecrease or eliminate patient pain which can be caused by harvestingexcessive amount of muscle tissue along with the tendon or by pushing aharvesting instrument with an excessive force within the patient's body.

FIG. 7 illustrates an example of a generally cylindrical hollow endeffector 706 having a tissue seating passage 714 extending therethrough.The end effector 706 can have a rounded or oval cross-sectional shape.The first and second ends 707 a, 707 b of the end effector 706 havedifferent shapes. Specifically, as shown, the first end 707 a configuredto harvest a tendon at its distal end has an extension 709 extendingfrom one wall of a hollow main body 705 of the end effector 706. Such aconfiguration can be suitable for deep and superior portions of thegracilis and semitendinosus tendons. In the illustrated example, theextension 709 is generally triangular or V-shaped. However, theextension can have other suitable configurations. Regardless of itsspecific configuration, the extension 709 can be sharp so as to be usedto cut the accessory attachments. The extension 709 will be interfacingwith a portion of the tendon where the accessory bands typically arise(superficial and inferior portions). At the same time, the remainder ofthe outer edge of the first end 707 a not occupied by the extension 709can be blunt, or dull, so as to protect the main trunk of the tendon andto avoid damaging sensitive anatomical structures or prematurelyamputating the tendon. Thus, when the end effector 706 is coupled to thetendon such that a portion of the tendon extends through the tissueseating passage 714, and the surgical instrument is moved along thetendon, the accessory bands will be guided by the extension 709 to thepoint where they are cut.

In the example of the end effector 706 of FIG. 7, the outer edge of thesecond end 707 b that is used to separate and cut the proximal end ofthe tendon can be uniform, such that it has no surface features and itis blunt or sharp uniformly throughout the outer edge. However, in someaspects, the second end 707 b can also have features that facilitateharvesting the tendon at the proximal end thereof.

FIGS. 8A-8F show one example of a method of harvesting a tendon 800using surgical instrument 100 (FIGS. 1A, 1B, 2A-2C, 3A, and 3B). Itshould be appreciated that the method is described in connection withthe surgical instrument 100 by way of example only, as another surgicalinstrument that can have any of the end effectors in accordance with thedescribed embodiments can also be used. The tendon 800 can be ahamstring tendon, such as the gracilis or semitendinosus tendon.

FIGS. 8A-8F illustrate medial views of a patient's knee 802 showing afemur 804, a patella 806, a tibia 808, and the tendon 800 to beharvested. The musculotendinous junction 810 of the tendon 800 thatremains in the patient after the tendon 800 is harvested is also shown.FIG. 8A shows the knee 802 and the tendon 800 having first (proximal,adjacent to the femur 804) and second (distal, attached to the tibia808) ends 800 a, 800 b before the surgical procedure begins. It shouldbe appreciated that the opposite ends of the tendon 800 are identifiedas the “first” and “second” ends for illustration purposes only, and notto show any particular order. As shown in FIG. 8B, before the surgicalinstrument 100 is being used, an incision 812 adjacent a mid-point ofthe tendon 800 is made. In the illustrated embodiment, the incision 812is a posterior incision made on the back of the patient's knee 802. Theincision 812 can be made using any suitable instruments and techniquesas known in the art.

After the incision 812 is made, the end effector 106, shown in detail inFIGS. 1A, 1B, 2A-2C, 3A and 3B, and shown only schematically in FIGS.8B-8E, is inserted into the incision 812 and coupled with the tendon800. This can be done, for example, by passing a portion of the tendon800 near the mid-point thereof around the first and second arcuatemembers 118 a, 118 b of the end effector 106 (e.g., FIG. 1B) such thatthe portion of the tendon 800 is seated within and extends through thetissue seating passage 114 defined by the end effector 106. Theposterior incision 812 allows proper access to the tendon such that thetendon 800 can be identified relatively easily. For example, a surgeonperforming the procedure can identify that the tendon 800 is thegracilis or semitendinosus tendon.

The end effector 106 is positioned with respect to the elongate shaft102 of the surgical instrument 100 such that the first end 107 a thereofis positioned to be a leading end and the second end 107 b is positionedas a trailing end, as shown in FIG. 3A. In such a configuration, the endeffector 106 is advanced proximally along the tendon 800 from themid-point towards the first end 800 a of the tendon 800, as shown inFIG. 8B. The surgical instrument 100 is operated such that the endeffector 106 is advanced proximally towards the musculotendinousjunction 810 and the first end 107 a (shown in FIG. 3A) operating as theleading end is used to strip the tendon 800 of muscle and othersurrounding tissue.

After the end effector 106 is advanced along a sufficient length of thetendon 800, the first end 107 a is then used to cut the tendon 800 atthe first end 800 a thereof near the musculotendinous junction 810. Inthis way, the first end 800 a of the tendon 800 is separated from itsattachment point on the muscle adjacent to the femur 804.

After the after the tendon 800 is cut at the first end 800 a thereof,the end effector 106, which remains coupled to the tendon 800, isreturned to the location near the incision 812, as shown in FIG. 8D. Theend effector 106 is advanced distally towards the point of the incision812. In the illustrated example, the end effector 106 (which remainscoupled to the tendon 800) can remain within the incision 812 andmanipulated such that the second end 107 b (shown in FIG. 3B) thereof ispositioned to be the leading end and the first end 107 a thereof ispositioned to be the trailing end, as shown in FIG. 3B. However, the endeffector 106 can also be retracted from the incision 812 and thenmanipulated such that the second end 107 b is positioned to be theleading end. The free first end 800 a of the tendon 800 can be withdrawnfrom the incision 812, as shown in FIG. 8D.

With its second end 107 b positioned to be the leading end (as shown inFIG. 3B), the end effector 106 coupled to the tendon 800 is advancedalong the tendon 800 in an opposite direction, from the location nearthe incision 812 towards the opposite, second end 800 b of the tendon,as shown in FIG. 8E. The second end 107 b of the end effector 106 isused to strip and cut the tendon 800 at the second end 800 b thereof.The tendon 800 is thus stripped off of the tibia 808 and is removed inits entirety via the incision 812 for subsequent processing as a graft.Thus, FIG. 8F illustrates the harvested tendon 800 separately from theknee 802. The incision 812 can then be closed using any suitabletechnique. Alternatively, another tendon can be harvested via theincision 812. For example, if the tendon 800 harvested first is one ofthe gracilis and semitendinosus tendons, another of the gracilis andsemitendinosus tendons can then be harvested. The configuration of theend effector 106 allows advancing it in a manner that decreases oreliminates a possibility of the end effector 106 being diverted from themain tendon 800.

It should be also appreciated that although the illustrated embodimentsprovide instruments and methods for harvesting a tendon for subsequentuse as a graft in a ligament reconstruction surgery involving fixationof anterior or posterior cruciate ligaments, the techniques can beadapted for harvesting other types of tendons and for other surgicalprocedures as well. For example, the described techniques can be usedfor harvesting other anatomical structures, such as, for example, nervesand veins.

Having thus described some examples of the described embodiments,various alterations, modifications, and improvements will readily occurto those skilled in the art. Such alterations, modifications, andimprovements are intended to be within the spirit and scope of thedescribed embodiments. Accordingly, the foregoing description is by wayof example only, and not intended to be limiting.

What is claimed is:
 1. A surgical instrument, comprising: an endeffector mounted on an elongate shaft, the end effector defining atissue passage configured to separate and receive a length of tissue,the tissue passage having a predefined and static shape; and a cuttingelement, wherein the end effector is pivotally mounted to the elongateshaft such that the end effector is configured to be rotatablymanipulated during a procedure.
 2. The surgical instrument of claim 1,wherein the cutting element is configured to cut the length of tissueseated in the tissue seating passage.
 3. The surgical instrument ofclaim 1, wherein the end effector includes a first arcuate member and asecond arcuate member.
 4. The surgical instrument of claim 3, whereinthe cutting element is a sharpened edge of at least one of the first andsecond arcuate members.
 5. The surgical instrument of claim 1, whereinthe cutting element is a sharpened protrusion extending from the endeffector and along an axis defined by the tissue seating passage.
 6. Thesurgical instrument of claim 1, wherein the tissue passage defines alongitudinal axis, and the cutting element is configured to cut tissuetransverse to the longitudinal axis.
 7. The surgical instrument of claim1, wherein a first end of the end effector is selectively positionableto be one of a leading end and a trailing end, wherein the leading endis distal a distal end of the elongate shaft and the trailing end isproximal the distal end of the elongate shaft.
 8. A surgical instrument,comprising: a tissue harvesting guide pivotally mounted on an elongateshaft, the tissue harvesting guide configured to separate and receive alength of tissue, and configured to selectively pivot over about a 180degree range of motion between a first position proximate a first sideof the elongate shaft and a second position proximate an opposed secondside of the elongate shaft, wherein a first end of the tissue harvestingguide is a leading end of the tissue harvesting guide when it is in thefirst position and wherein the first end of the tissue harvesting guideis a trailing end of the tissue harvesting guide when it is in thesecond position, and wherein the leading end is distal to a distal endof the elongate shaft and wherein the trailing end is proximal to adistal end of the elongate shaft.
 9. The surgical instrument of claim 8further comprising a cutting element.
 10. The surgical instrument ofclaim 8, wherein the tissue harvesting guide includes a first extensionand a second extension, wherein the first and second extensions define atissue passage therebetween.
 11. The surgical instrument of claim 10,wherein the cutting element is a sharpened edge of at least one of thefirst and second extensions.
 12. The surgical instrument of claim 8,wherein the tissue harvesting guide defines a longitudinal axis and thecutting element is configured to cut tissue in a direction transverse tothe longitudinal axis.